diff --git a/optimtool/__init__.py b/optimtool/__init__.py
index 3675a48..a6ef526 100644
--- a/optimtool/__init__.py
+++ b/optimtool/__init__.py
@@ -32,4 +32,4 @@
 from ._version import __version__
 
 if sys.version_info < (3, 7, 0):
-    raise OSError(f'optimtool-2.8.0 requires Python >=3.7, but yours is {sys.version}')
\ No newline at end of file
+    raise OSError(f'optimtool-2.8.1 requires Python >=3.7, but yours is {sys.version}')
\ No newline at end of file
diff --git a/optimtool/_version.py b/optimtool/_version.py
index f587d31..b9b1210 100644
--- a/optimtool/_version.py
+++ b/optimtool/_version.py
@@ -18,4 +18,4 @@
 # OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 # SOFTWARE.
 
-__version__ = '2.8.0'
\ No newline at end of file
+__version__ = '2.8.1'
\ No newline at end of file
diff --git a/setup.py b/setup.py
index 6782b19..82e52c8 100644
--- a/setup.py
+++ b/setup.py
@@ -4,7 +4,7 @@
 from setuptools import setup
 
 if sys.version_info < (3, 7, 0):
-    raise OSError(f'optimtool-2.8.0 requires Python >=3.7, but yours is {sys.version}')
+    raise OSError(f'optimtool-2.8.1 requires Python >=3.7, but yours is {sys.version}')
 
 if (3, 7, 0) <= sys.version_info < (3, 8, 0):
     # https://github.com/pypa/setuptools/issues/926#issuecomment-294369342